Increasing populations and climate change are causing ever increasing strains on water resources and drinking water supplies. In recent times this has resulted in water restrictions for households and businesses and increasing prices. It is therefore desirable to conserve water resources and avoid waste. Particularly in domestic situations large volumes of water can be wasted during the simple act of washing using hot water and waiting for hot water supply, for example, showering or washing hands under running water.
Water saving systems have been developed to recover and reuse waste water, often referred to as to grey water systems. Where a grey water system is installed, all water used for washing can be recovered in the grey water system, including the clean water that goes down the drain while waiting for hot water. Some grey water systems perform some treatment of the waste water and others simply store the waste water for a secondary use. Due to health concerns restrictions are generally imposed on the use of grey water, for example limiting use to flushing of toilets, watering of gardens and maybe for laundry use. Installation and use may also be restricted to ensure that grey water will not enter storm water drains. Grey water systems can be expensive and complex to install; requiring significant space for a large grey water storage tank and pump and significant re-plumbing for effective collection and reuse of recycled water. Ongoing maintenance is also required, for example regular changing of filters and servicing of pumps.
Other systems have been devised to recover fresh water that would otherwise be wasted before this goes down the drain to be treated as waste water. Known systems utilize temperature sensitive valves in hot water pipes to divert water from hot water pipes until the water reaches a threshold temperature. The diverted water is diverted to a holding tank. The water from the holding tank can then either be redirected into cold water supply pipes or used for another purpose such as watering gardens or flushing of toilets, similar to grey water use. Such systems recover water before it is released from the tap for diversion into the cold water circulation or another purpose and thus require significant re-plumbing for installation. Further because these systems use temperature sensing valves they may require regular maintenance. There is a need for simpler low maintenance systems to reduce wasting water.